Skip to content Skip to navigation

Petra Persson looks at what an A can really be worth

November 16, 2015

Grade inflation is a hot topic in education circles. An A was once a mark of distinction. Now, at many schools, it’s the new normal. What’s not clear though is what the effects of this practice might be. Is it a harmless boost to student self-esteem or does it unfairly tilt the education and employment playing fields to the advantage of those whose grades get inflated?

Petra Persson, an assistant professor of economics and a faculty fellow at the Stanford Institute for Economic Policy Research, has used the tools of economic analysis to examine this question in her home country of Sweden. In unpublished research conducted with faculty fellow and a Stanford Graduate School of Business economist Rebecca Diamond, Persson found that inflating grades when students were 16 had big effects in later life. Those whose grades got bumped up were more likely to complete high school and go to a university than students whose grades weren’t inflated, opening the way to higher income when they entered the job market.

“This is the first economic evidence of the long-term consequences of grade inflation,” says Persson, who earned her PhD from Columbia and specializes in public economics and social insurance. “We found a ripple effect throughout the educational career, putting inflated students on a different trajectory and potential earnings profile.”

In their study, Persson and Diamond exploited special features of Sweden’s educational system. In ninth grade, students take a series of standardized tests they must pass to qualify for high school. The researchers looked specifically at math results of more than 600,000 students who took the tests between 2004 and 2010. Tests were graded locally. Math results were based mostly on correct answers, but teachers could add points for subjective reasons, such as “clarity of expression.” In some districts, Persson and Diamond found no evidence of inflation, but in others they noticed discontinuities. For example, math scores in some places clustered just beyond the pass threshold, suggesting that teachers awarded extra points so students would get passing marks.

Being bumped up to a passing grade was no small thing. Statistical analysis showed that getting pushed above the pass threshold raised the likelihood of high school graduation by about 28 percentage points and ultimately led to higher-paying job opportunities. Moreover, pupils who completed high school because their test scores were graded up in ninth grade were more than twice as likely to have begun college five years later. The analysis also identified a possible motive for grade inflation—school competition. In Sweden, parents and kids choose their schools, which gives institutions in the most competitive districts incentive to raise student test scores. “These large differences in grade inflation undermine the equality of opportunity in Swedish schools,” says Persson. “Some pupils get bumped up a lot—with large long-term gains to follow—whereas others with the same ability, who simply happen to attend schools that grade less leniently, are left behind.”

Persson earned her PhD from Columbia and came to Stanford in 2013 as a SIEPR postdoctoral fellow. She describes her year at SIEPR as a terrific opportunity to focus on research without distractions and says she continues to benefit from interactions with the institute’s postdocs and visiting scholars. Since coming to the United States as a graduate student, Persson has lived in New York and Boston as well the Bay Area. She says her current home, Menlo Park, is similar to her hometown outside Lund in southern Sweden. Like Menlo Park, Lund is a small city in the shadow of two big cities, Copenhagen and Malmo. The pace of life in Menlo Park and Lund is more manageable than in the large metropolises where she has lived. She adds though that the winters are rougher in Lund and admits it’s much harder to find a burrito there.